Universal Tool Bit Shank

ABSTRACT

A universal tool shank can include an elongate body having first and second portions. The first portion can include at least one flat thereon for engagement with a recess in a first tool. The second portion can include at least one protrusion extending radially outwardly therefrom for engagement with a recess in a second tool. The first and second portions can be disposed axially apart from one another.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.11/322,183, filed Dec. 29, 2005, now pending, titled “Universal Tool BitShank,” which is incorporated by reference.

FIELD

The present disclosure relates to tools, and more particularly to toolshanks.

BACKGROUND

The statements in this section merely provide background informationrelated to the present disclosure and may not constitute prior art.

A variety of tool bits are available for use with drivers. However,these tool bits often have unique engagement portions. The drivers alsooften have a unique tool bit receiving portion. As a result, a tool bitthat is able to be coupled to one type of driver may not be able to becoupled to a different type of driver.

SUMMARY

A universal tool shank can include an elongate body having first andsecond portions. The first portion can include at least one flat thereonfor engagement with a recess in a first tool. The second portion caninclude at least one protrusion extending radially outwardly therefromfor engagement with a recess in a second tool. The first and secondportions can be disposed axially apart from one another.

Further areas of applicability will become apparent from the descriptionprovided herein. It should be understood that the description andspecific examples are intended for purposes of illustration only and arenot intended to limit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustration purposes only and arenot intended to limit the scope of the present disclosure in any way.

FIG. 1 is a plan view of a tool, a chuck assembly, and a tool bit inaccordance with the present disclosure;

FIG. 2 is a perspective view of the chuck assembly of FIG. 1;

FIG. 3 is a longitudinal or axial cross-sectional view taken generallyalong line 3-3 of FIG. 1, illustrating a tool bit prior to insertioninto the chuck assembly;

FIG. 4 is a longitudinal cross-sectional view similar to that of FIG. 3,but illustrating the tool bit fully inserted in the chuck assembly;

FIG. 5 is a lateral or radial cross-sectional view, taken generallyalong line 5-5 of FIG. 4;

FIG. 6 is a side view of a body portion of the chuck assembly;

FIG. 7 is a perspective view of a tool assembly;

FIG. 8 is a partial perspective view of a driver; and

FIG. 9 is a partial sectional view of an additional driver.

DETAILED DESCRIPTION

The following description is merely exemplary in nature and is notintended to limit the present disclosure, application, or uses.

FIGS. 1 through 6 depict an exemplary embodiment of a chuck assembly ortool bit holder according to the present disclosure, shown merely forpurposes of illustration. One skilled in the art will readily recognize,from the following discussion and the accompanying drawings, that chuckassemblies or bit holders of configurations other than that of thisexemplary illustration can also advantageously employ the principles ofthe present disclosure.

In FIGS. 1 through 6, an exemplary chuck assembly or bit holder 10 isattachable to a power tool or to a hand tool 18 to be driven forrotation about an axis 12 (shown in FIG. 3). The chuck assembly 10 isadapted to removably receive a tool bit 14 having a generally hex-shapedshank 15 with a circumferential recess 16 formed therein. The tool bit14 can be any of a number of well-known bits, including drill bits, nutdriver bits, screwdriver bits, or other types of fastener driver bits,for example.

As best shown in FIGS. 3 and 6, the chuck assembly 10 generally includesa body 20, having a shank portion 22 thereon for mounting the chuckassembly 10 for rotation by a hand tool or a power tool. A hex-shapedsocket or bore 24 is formed in the body 20, with the bore 24 openingaxially outwardly toward the front or forward end of the chuck assembly10. A pair of annular retainer grooves 26 a, 26 b are provided atopposite ends of a cylindrical main body portion 20 a of the body 20 (asbest shown in FIG. 6). A plunger bore 28 extends axially from thehex-shaped socket or bore 24 toward the rear end of the chuck assembly10.

A generally cylindrical hollow retraction collar 30 surrounds a portionof the radially outer periphery of the body 20 and is axially slidablethereon. The hollow retraction collar or sleeve 30 includes a radiallyinwardly-directed forward flange 32 slidably surrounding a portion ofthe body 20, with a hollow internal bore 34 within the retraction collar30 opening in an axially-rearward direction and being of a diametersufficient to slidably surround an annular bearing sleeve 36 mounted onthe rear end of the main body portion 20 a of the body 20. The bearingsleeve 36 abuts against a retention ring 38 received in the rearwardretainer groove 26a of the body 20.

The body 20 includes an angular slot 50 formed transversely therein,with the slot 50 extending from the radially outer surface of the body20 in an axially forward and radially inward direction to communicatewith the interior of the hex bore or socket 24. A generally U-shapedretaining clip 60 has a central base portion 62 and a pair of legs 64 atopposite ends of the central base 62 forming opposite corners 66thereon. The base 62 of clip 60 is slidably disposed within the angularslot 50, and the two legs 64 extend around the body 20 to locationsthereon that are on an opposite side of the axis 12 from the base 62 andthe slot 50.

A coil spring 40 surrounds a portion of the body 20 and is disposedbetween the body 20 and the retraction collar 30. The coil spring 40abuttingly engages the annular bearing sleeve 36 and directly engagesthe clip 60. Thus compressed, the coil spring 40 resiliently biases theclip 60 in forward axial and inward radial directions within the slot50. Because of this direct abutting engagement with the clip 60 and itslegs 64 (as discussed above), the resultant reactive axial force exertedby the clip 60 on the coil spring 40 is directed substantially along theaxis 12, thus keeping the coil spring 40 coaxially aligned with the body20.

As can best be seen in FIGS. 3 through 5, the clip 60 is retractedaxially rearwardly and radially outwardly in the slot 50, during axiallyrearward retraction of the retraction collar 30. At the end of thisretraction, the corners 66 (at the intersections of the legs 64 with thecentral base 62) move radially outwardly into contact with the internalsurface of the internal hollow bore 34 of the retraction collar 30. Thiscontact substantially prevents further axially rearward movement of theretraction collar 30, thus substantially minimizing the possibility ofover-retraction and subsequent cocking or jamming of the retractioncollar 30.

Still further, in accordance with the preferred form of the presentinvention, the coil spring 40 has at least one bight at each of itsforward and rearward ends axially collapsed to form respective forwarddead coil bights and rearward dead coil bights. This dead coil end bightarrangement can optionally be provided at either the forward or rearwardends of the coil spring 40, or preferably at both ends. Such dead coilbights at the ends of the coil spring 40 allow the coil spring 40 toengage the step on the body 20 and the legs 64 of the clip 60,respectively, in a substantially flat abutting relationship therewith.This, in turn, serves to help maintain the coil spring 40 in a proper,coaxially-aligned relationship with the body 20 and helps eliminate theneed for any of the prior art's intermediate sliding sleeves or othersuch intermediate members between the coil spring 40 and the clip 60.Thus, this arrangement helps eliminate the need for a flat portion onsuch an intermediate sleeve or member and a corresponding flat portionon the body 20 in order to keep such an intermediate sleeve or othersuch member properly aligned. This dead coil end bight arrangement,along with the other features of the chuck assembly 10 described above,all contribute to the increased simplification and decreased cost ofmachining and assembling the chuck assembly 10, as well as helping tominimize the number of required parts.

A retention ring 68 is preferably fixed in the forward retaining groove26 b at the forward end of the body 20 and thus serves to retain theabove-described components in their assembled condition. The retentionring 68 is preferably in the form of a C-shaped clip ring.

A plunger 70 is received in the plunger bore 28 of the body 20. Theplunger 28 is cylindrical or capsule shaped including an annular flangeportion 72 extending radially outward from a center portion of theplunger 70. The annular flange portion 72 contacts the generallycylindrical inner wall surface of the plunger bore 28. A plunger spring74 is received within the plunger bore 28 and abuts against a rearwardwall thereof and against the annular flange 72 of the plunger 70. Aplunger bearing 76 is provided to retain the plunger 70 within theplunger bore 28. The plunger bearing 76 has an annular ring shape whichis received in the forward end of the plunger bore 28 and receives aforward end of the plunger 70 through an annular opening therein. Theplunger bearing 76 can be press-fit or otherwise fastened within the endof the plunger bore 28. The flange 72 of the plunger 70 abuts againstthe plunger bearing 76 when there is no bit received within the chuckassembly 10, as best shown in FIG. 3.

As a bit 14 is inserted into the chuck assembly 10, as shown in FIG. 4,the end of the bit 14 presses against the forward end of the plunger 70pressing the plunger rearward as illustrated in FIG. 4. The plunger ispressed against the spring force of the spring 74 into a retractedposition. As the tool bit 14 is pressed inward, the retaining clip 60 isforced to slide rearwardly and radially outwardly in the angular slot50, against the bias of the coil spring 40, in order to allow the bit tobe inserted. Once the bit is fully seated in the hex socket 24, the baseportion of the retaining clip 60 is resiliently urged back downwardtowards the bottom of the angular slot 50 where it engages thecircumferential recess 16 formed on the hex shank 15 of the bit 14. Thetool bit 14 is removed from the chuck assembly 10 by the operatorsliding the retraction collar 30 axially rearwardly along the body 20thus compressing the coil spring 40 to allow the retaining clip 60 toretract back up the angular slot 50 and release the tool bit 14 as thetool bit is pressed outward by the plunger 70. The spring force of theplunger spring 74 is preferably selected so as to press the bit forwardenough with the centerline of the bit extending vertically so that thecircumferential recess 16 in the hex shank 15 is pressed forward so asto prevent re-engagement by the retaining clip 60 when the retractioncollar 30 is released by the operator. However, the spring force is alsoselected to be weak enough so as not to eject the bit from the hexsocket. Specifically, the spring force is preferably weak enough toprevent ejection of the bit when the centerline of the bit is tendegrees below horizontal (−10 degrees from horizontal). Thus, anoperator can hold the tool 18 with one hand, pull the retraction collar30 to a released position with the other hand, and then release theretraction collar and pull the tool bit out of the hex socket 24 whilemaintaining control of the tool 18 with the first hand. The removal ofthe bit can be accomplished in this manner while the tool is positionalsuch that the centerline of the bit is above −10 degrees from horizontalwithout the bit falling out.

As seen in FIGS. 1 and 2, shank 22 is a universal shank and includesfirst and second portions 124, 126. The first portion 124 has agenerally hexagonally shaped cross-section with flats 128 thereon.Second portion 126 is located between first portion 124 and sleeve 30.The first portion 124 can optionally be provided with a recessed annularball groove 124A provided in the exterior surface as shown in phantom inFIG. 6.

Second portion 126 includes a generally cylindrical body 132 having adiameter greater than the diameter of first portion 124. Retaining arms134 extend radially from cylindrical body 132. The arms 134 extendgenerally axially along a portion of the cylindrical body 132,terminating before first portion 124. An additional retaining assembly136 is also located in second portion 126.

Retaining assembly 136 includes a ball 138 and a spring 140 and isretained within recess 142. Recessed portion 142 includes an outeropening 144 having a diameter less than the diameter of ball 138 and aninner portion 146 having a diameter greater than the diameter of ball138. The spring 140 biases the ball 138 radially outwardly, forcing ball138 against outer opening 144. Outer opening 144 generally limits theradial travel of ball 138. Retaining assembly 136 can therefore providean additional engagement with a receiving bore having a recess therein,as seen in FIG. 9 and discussed below.

Alternatively, as seen in FIG. 7, a tool assembly 210 can include a toolmember 220 having a shank 222 thereon for mounting the tool assembly 210for rotation by a hand tool or a power tool. The tool member 220 isshown as a common screwdriver having a head 226 and a shaft 224.However, it is understood that any number of tools can be substitutedfor the screwdriver shown in FIG. 7. Shank 222 is generally identical toshank 22, and therefore will not be described in detail. As such, shank22 is discussed below with the understanding that the following equallyapplies to shank 222.

Shank 22 is universal due to first and second portions 124, 126 beingdesigned to be used with different tools. Shank 22 can be received by avariety of drivers having tool receiving recesses such as those shown inFIGS. 8 and 9.

As seen in FIG. 8, a first driver 230 can include a body 232 having anend surface 234 and a hexagonal shaped recess 236 extending therethroughand into the body 232. In this arrangement, first portion 124 can extendinto recess 236 and second portion 126 can generally abut end surface234, thereby providing a driving engagement between driver 230 and chuckassembly 10.

As seen in FIG. 9, a second driver 238 can include body 240 having anend surface 242 and a generally cylindrical recess 244 extendingtherethrough and generally into the body 240. Axially extending slots246 are formed in cylindrical recess 244 and include an end surface 248.A recess 250 is also located in cylindrical recess 244. Shank 122 canextend into cylindrical recess 244. Due to its smaller diameter, firstportion 124 can extend freely through cylindrical recess 244 and secondportion 126 can engage cylindrical recess 244 through arms 134 and ball138. Arms 134 can be located within slots 246 and abut end surfaces 248.Ball 138 can additionally be located within recess 250.

1. A tool bit holder comprising: a body portion defining a longitudinalbore for receiving a tool bit therein, wherein the body portion furthercomprises a holding member that is biased into the bore to retain thetool bit in the bore; and a universal shank portion extending from saidbody portion and including first and second portions, said first portionhaving at least one flat thereon, said first portion being removablyengageable directly with a recess in a first tool such that said secondportion extends axially away from said first tool, said second portionhaving at least one protrusion extending radially outwardly therefrom,said second portion being removably engageable directly with a recess ina second tool such that said first portion is received within saidrecess in said second tool with said at least one protrusion beingreceived in at least one corresponding radial slot that extends radiallyfrom said recess in said second tool, said first and second portionsdisposed axially apart from one another.
 2. The tool bit holder of claim1, wherein said first portion includes a hexagonal cross section.
 3. Thetool bit holder of claim 1, wherein said at least one protrusionincludes a plurality of radially extending protrusions uniformlydistributed about said second portion.
 4. The tool bit holder of claim3, wherein said radially extending protrusions include first and secondarms extending from said second portion generally opposite one another.5. The tool bit holder of claim 1, wherein said second portion islocated between said body portion and said first portion.
 6. The toolholder of claim 1, further comprising a retaining member displaceablycontained within said shank and biased radially outwardly, saidretaining member including a portion extending past an outer surface ofsaid shank when in an unengaged position.
 7. The tool holder of claim 2,wherein said first portion includes a ball groove therein.
 8. The toolbit holder of claim 1, wherein the second portion is disposed betweenthe body portion and the first portion.
 9. The tool bit holder of claim1, wherein the body portion further comprises a sleeve that is moveablein the axial direction to release the holding member from engaging thetool bit.
 10. The tool bit holder of claim 9, wherein the holding membercomprises a spring and a wire form that extends through an angled slotinto the bore.
 11. The tool holder of claim 1, wherein said firstportion includes a ball groove therein.